EXPERIMENTAL ANALYSIS OF FLOW REGIMES PERTAINING TO ELECTROSPINNING FROM A POLYMER DROP

Abstract

The fluid dynamics of an electrospun polymer jet is thoroughly analyzed, and strategies for the effective control of electrospinning for the production of fibers are proposed. Flow regimes such as Taylor cone, straight section, and bending/higher-order instabilities of the electrospun jet are systematically analyzed. Dimensional analysis has been performed to formulate correlation formulae, which govern the characteristics of the Taylor cone and the straight section of the jet. Time-resolved images enabled the effects of the salient operating parameters on bending instability to be systematically investigated. The failure modes of the electrospun jet during bending instability have also been investigated. Linear stability analyses incorporating non-Newtonian effects have been performed to characterize higher-order instabilities. Techniques for the effective control of electrospinning have been proposed. In the first technique, a pulsed laser is used to overcome surface tension and produce an electrified jet. Another technique proposed yields regular-sized microfibers through near-field electrospinning.